The present invention relates to novel metallocene compounds, their intermediates and their preparation. Specifically the invention relates to transition metal metallocenes with heteroatom 1- or 3-substituted indenyl and indenyl derivative ligands and a method for their preparation. The invention also relates to 1- or 3-substituted indene compounds as intermediates for the metallocene compounds and their preparation. Further, the invention relates to the use of said metallocenes in catalyst systems for the homo- and copolymerization of ethylenically unsaturated monomers, preferably olefins, more specifically propylene, ethylene and higher alphaolefins, especially in the presence of a cocatalyst, such as methylaluminoxane (MAO).
Chiral C2 symmetric bis(indenyl) ansa-metallocenes are well-known catalyst components for stereoselective polymerization of alpha-olefins. The performance characteristics of these systems are different, the variations being induced by size and position of the substituents. E.g., dimethylsilylene bridged 2,2xe2x80x2-dimethyl-4,4xe2x80x2-diaryl substituted bis(indenyl) zirconocenes developed by Brintzinger and coworkers (Organometallics 1994, 13, 964) and Spaleck et al. (Organometallics 1994, 13, 954), produce isotactic polypropylenes with catalyst activities and polymer properties comparable to those obtained with heterogeneous Ziegler-Natta catalysts.
The area of electronically altered bis(indenyl) metallocenes has remained relatively unexplored. Previously, it has been reported that halogen or alkoxy substitution in the six-membered rings of indenes reduces the activity of the catalyst system and the molecular weight of the produced polymer (Consiglio et al, Organometallics 1990, 9, 3098; Collins et al., Organometallics 1992, 11, 2115). Bis(indenyl) zirconocenes with 2-amino functionalized ligands have been reported recently by several groups (Luttikhedde et al., Organometallics 1996, 15, 3092; Plenio and Burth, J. Organomet. Chem. 1996, 519, 269; Brintzinger et al., J. Organomet. Chem. 1996, 520, 63). The bridged complexes show somewhat lower catalytic activities compared with their unsubstituted bis(indenyl) zirconocene analogues.
It has now been found however that metallocenes in which a bulky electron withdrawing or donating group is attached to the five membered ring of an indenyl or indenyloid (ie. indenyl analog) ligand have particularly interesting properties, in particular in terms of catalytic activity when used with an alumoxane cocatalyst in propylene and ethylene polymerization.
Thus viewed from one aspect the invention provides a metallocene having a sandwich bonding having ligand comprising a sandwich bonding moiety, having an unsaturated 5-membered ring or a 6-membered ring fused to an unsaturated 5-membered ring, which is covalently substituted by a pendant group containing at least two atoms other than hydrogen and attached via an atom other than a methylene carbon, preferably attached via an oxygen, sulphur, nitrogen or phosphorus atom or via a carbonxe2x80x94carbon multiply bonded carbon atom, eg. a group as described below or in FI 970349 the contents of which are incorporated herein by reference. The sandwich bonded metal in the metallocene is preferably a Group 4 transition metal, particularly Zr, Hf or Ti, most preferably Zr. Other catalytically effective metals however may be used.
By pendant it is meant that the bulky substituent is not attached to a second group which sandwich bonds the metal of the metallocene.
The requirement that the group contains at least two non-hydrogen atoms simply specifies a minimum bulk for the required bulky substituent. Thus halogens and unsubstituted hydroxyl and amine groups are excluded for example. Preferably the substituent contains up to 32 non-hydrogen atoms. The requirement that the group be attached other than via a methylene carbon indicates that the substituent will interact with the electron system of the five membered ring. Suitable means of attachment include oxygen, sulphur, nitrogen and phosphorus atoms and II-bonded carbon atoms. Oxygen attachment is preferred. The attachment atom preferably carries at least one bulky substituent, eg. a C1-20 hydrocarbyl group, or more preferably a silyl group or a germyl group, with the silicon or germanium atoms themselves optionally being substituted by C1-20 hydrocarbyl or hydrocarbyloxy groups.
The fused 5 and 6-membered rings in the sandwich bonding ligand may be homocyclic (carbocyclic) or heterocyclic, for example containing up to 4 ring heteroatoms selected from O, N and S. The four atom bridge portion of the six membered ring may be unsaturated or saturated. Both the 5 and 6-membered ring may carry other homo- or heterocyclic fused rings. The bulky substituent may be at the 1, 2 or 3 position of the 5-membered ring, eg. the 1- or 3-positions. Particularly preferably the ligand contains two such fused 5/6 member ring systems linked via a bridging atom or group (eg. an ethylene bis indenyl ligand).
In the case where the bulky substituent is a silyloxy or germyloxy group, it is possible for this to be on the 6-membered rather than the 5-membered ring. This represents a further aspect of the invention. Viewed from this aspect the invention provides a metallocene catalyst precursor having a sandwich bonding ligand which comprises a sandwich bonding moiety having an unsaturated 5-membered ring or having a 6-membered ring fused to an unsaturated 5-membered ring, said moiety being substituted on the fused ring structure by a silyloxy or germyloxy group, eg. at the 1, 3, 4, 5, 6 or 7 positions. Germanium atom is further substituted by a C1-20 hydrocarbyl or hydrocarbyloxy group.
These ligands themselves are novel and form a further aspect of the invention. Viewed from this aspect the invention provides a sandwich bonding ligand precursor comprising a moiety having a 6-membered ring fused to an unsaturated 5-membered ring, said moiety being substituted on the fused ring structure by a silyloxy or germyloxy group.
The polymerization activity of the metallocene precursors of the invention is such that it is possible to use as a cocatalyst higher alkyl alumoxanes than the conventionally used methyl alumoxane (MAO). By a higher alkyl alumoxane is meant one containing alkyl groups containing 2 or more, eg. 2-10, carbons. This is highly advantageous since the higher alumoxanes are better characterised than MAO which appears to be a mixture of various compounds.
Thus viewed from a further aspect the invention provides a catalyst system comprising or produced by the reaction of a metallocene catalyst precursor according to the invention and an alkyl alumoxane comprising alkyl groups containing at least two carbon atoms, preferably a heterogeneous catalyst system further comprising a support material.
Viewed from a still further aspect the invention provides a method for the preparation of a heterogeneous catalyst system, said method comprising contacting a porous solid (eg. particulate) support, preferably an inorganic support such as silica or alumina, with (i) a higher alkyl alumoxane and a metallocene according to the invention or with the reaction product of a higher alkyl alumoxane and a metallocene according to the invention, and optionally (ii) an organometallic metallocene-activator.
In this method, an activator (optional component (ii)) will be used if the metallocene used requires activation, eg. where it does not contain any alkyl ligands. In this regard, the process described in FI 970349 and analogous processes are applicable.
Viewed from a yet still further aspect the invention provides a process for the catalysed polymerization of an olefin, wherein as catalyst is used a metallocene and a cocatalyst (preferably an alumoxane, especially preferably a higher alkyl alumoxane), or the reaction product of a metallocene and an alumoxane, the improvement comprising using as said catalyst a said cocatalyst and a metallocene according to the invention or a reaction product thereof.
The invention will now be described in more detail using as illustrative members of the metallocenes according to the invention those in which the sandwich bonding ligand is a silyloxy or gemyloxy indenyl (or indenyloid) ligand.
Thus the present invention concerns novel metallocene compounds, substantially characterized by the formula (I):
(CpYq)mMRnBoxe2x80x83xe2x80x83(I)
wherein: Cp or each same or different Cp is a non-substituted or substituted, fused or non-fused, homo(iso)cyclic or heterocyclic cyclopentadienyl ligand, indenyl ligand, tetrahydroindenyl ligand, fluorenyl ligand or octahydrofluorenyl ligand, Y or each same or different Y is a substituent at the cyclopentadienyl ring of said ligand Cp having the following structure (II): 
wherein: D is an element of Group 14 of the Periodic Table (IUPAC), R1, R2 and R3 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or at least two of R1, R2 and R3 form together with D a C4-C20 ring structure; M is a transition metal of Group 4 of the Periodic Table (IUPAC) and is bound to the ligand Cp or ligands Cp in an xcex75 bonding mode; R or each same or different R is bound to M and is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or two R form together with M a C4-C20 metallocyclic ring structure: B is a bridge atom or group between two Cp ligands or between one Cp ligand and M; q is, when Cp is non-bridged, 0-5 for the cyclopentadienyl ligand, 0-3 for the indenyl or tetrahydroindenyl ligand and 0-1 for the fluorenyl or octahydrofluorenyl ligand, q is, when Cp is bridged, 0-4 for the cyclopentadienyl ligand, 0-2 for the indenyl or tetrahydroindenyl ligand and 0 for the fluorenyl or octahydrofluorenyl ligand; m is 1 or 2; mxc2x7qxe2x89xa71; o is 0 or 1; and n is 4-m-o, except when there is one bridge B between two Cp ligands, in which case n is 4-m.
The ligand Cp or each of the ligands Cp of the metallocene compound of formula (1) is preferably a mono- or polysubstituted, non-fused, homocyclic indenyl or tetrahydroindenyl ligand.
The substituent Y or each of the substituents Y preferably has the above structure (II), wherein D is silicon or germanium, preferably silicon. Preferably, but independently, the substituent Y or each of the substituents Y has the above structure (II), wherein R1, R2 and R3 are the same or different and are each an unsubstituted C1-C10 hydrocarbyl group, preferably wherein two of R1, R2 and R3 are linear C1-C4 alkyl groups such as a methyl group and one of R1, R2 and R3 is a branched C3-C10 alkyl group such as an isopropyl group, a tert-butyl group or a thexyl group, a C5-C8 cycloalkyl group such as a cyclohexyl group, or a C6 aryl group such as a phenyl group. According to another embodiment, all three groups R1-R3 are branched C3-C10-alkyls, such as isopropyl groups.
In the metallocene according to the present invention, the transition metal M of formula (I) preferably is zirconium. In the above formula (I) the group or groups R are bound to the transition metal M. R, or each R independently is one of an unsubstituted C1-C4 alkyl group, preferably a methyl group, or a halogen, preferably chlorine.
According to one embodiment of the invention B is a bridge atom or group between two Cp ligands, preferably a substituted or unsubstituted C1-C10 alkylene, a C2-C8 silylene or a C1-C10 alkylene-C2-C8 silylene, and most preferably ethylene or dimethylsilylene. According to another embodiment of the invention, B is a bridge atom or group between one Cp ligand and M, preferably a bridge of the structure xe2x80x94(ERxe2x80x22)pxe2x80x94Zxe2x80x94, wherein each E is independently a carbon, a silicon or a germanium, Z is xe2x80x94NRxe2x80x3xe2x80x94, xe2x80x94PRxe2x80x3xe2x80x94, xe2x80x94Oxe2x80x94 or xe2x80x94Sxe2x80x94, most preferably xe2x80x94NRxe2x80x3xe2x80x94, each Rxe2x80x2 being independently a hydrogen, each Rxe2x80x2 and Rxe2x80x3 being independently a substituted or unsubstituted C1-C10 hydrocarbyl, said xe2x80x94(ERxe2x80x22)-end preferably being bound to Cp and said xe2x80x94Z-end being bound to M. Compound having such bridges, but lacking the structure (II), are disclosed e.g. in WO 93/14132, p. 2, 1. 20-p. 6, 1. 17, herewith included by reference to define said bridge B.
The metallocene compound according to the invention preferably does not have a group CpYq wherein Cp is an indenyl or tetrahydroindenyl ligand monosubstituted (q=1) by Y at its 2-position, the D of Y being silicon or germanium; except when it has a second group CpYq, wherein Cp is an unsubstituted ligand (q=0) bridged by B to said first group CpYq.
The Cp of the metallocene according to formula (I) is preferably an indenyl or tetrahydroindenyl ligand substituted by Y in at least its 1- or 3-position. The numbering 1 or 3 depends on the substituent Y and the bridge B. If Y is bound to Cp alone or with a higher atom than B, then Y is in the 1-position. If Y is bound to Cp with a lower atom than B, then Y is in the 3-position. More preferably the metallocene has the formula (IIIa) or (IIIb): 
wherein: each Y is the same as above, each Yxe2x80x2 is as defined for Y; R4, R5, R6, R7, R9, R10, R11, R12, R4xe2x80x2, R5xe2x80x2, R6xe2x80x2, R7xe2x80x2, R9xe2x80x2, R10xe2x80x2, R11xe2x80x2, R12xe2x80x2 are the same or different and are each one of a hydrogen a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, at least two adjacent groups of R4-R7 or R9-R12 in formula (IIIa) may form at least one aromatic C6 ring, at least two groups of R4-R7 or R9-R12 in formula (IIIa) may form at least one aliphatic C5-C8 ring, one pair of equally numbered groups and another adjacent pair of equally numbered groups of R4xe2x80x2-R7xe2x80x2 or R9xe2x80x2-R12xe2x80x2 in formula (IIIb) may form an aromatic C6 ring, or at least two groups of R4xe2x80x2-R7xe2x80x2 or R9xe2x80x2-R12xe2x80x2 in formula (IIIb) may form at least one aliphatic C5-C8 ring, R8, R13, R8xe2x80x2 and R13xe2x80x2 are the same or different and are each one of a hydrogen atom, a halogen atom, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group or the group Y; N is the same as above in formula (I), Mxe2x80x2 is as defined for M; B is a bridge between two Cp ligands as defined above in formula (I), Bxe2x80x2 is as defined for B; each R is the same as above in formula (I) and each Rxe2x80x2 is as defined for R.
Particularly preferred bridged 1- or 3-(siloxy)indenyl and 1- or 3-(siloxy)-4,5,6,7-tetrahydroindenyl metallocenes according to the present invention include: rac- and meso-[ethylenebis(1-(tert-butyldimethylsiloxy)indenyl)]zirconium dichloride; rac- and meso-[dimethylsilylenebis(3-(tert-butyldimethylsiloxy)indenyl)]zirconium dichloride; rac- and meso-[ethylenebis(1-(thexyldimethylsiloxy)indenyl)]zirconium dichloride; rac- and meso-[dimethylsilylenebis(3-(thexyldimethylsiloxy)indenyl)]-zirconium dichloride; rac- and meso-[ethylenebis(1-(tert-butyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]zirconium dichloride; rac- and meso-[dimethylsilylenebis(3-(tert-butyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]zirconium dichloride; rac- and meso-[ethylenebis(1-(thexyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]zirconium dichloride and rac- and meso-[dimethylsilylenebis(3-(thexyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]zirconium dichloride; and the same hafnium compounds such as: rac- and meso-[ethylenebis(1-(tert-butyldimethylsiloxy)indenyl)]hafnium dichloride; rac- and meso-[dimethylsilylenebis(3-(tert-butyldimethylsiloxy)indenyl)]hafnium dichloride; rac- and meso-[ethylenebis(1-(thexyldimethylsiloxy)indenyl)]hafnium dichloride; rac- and meso-[dimethylsilylenebis(3-(thexyldimethylsiloxy)indenyl)]hafnium dichloride; rac- and meso-[ethylenebis(1-(tert-butyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]hafnium dichloride; rac- and meso-[dimethylsilylenebis(3-(tert-butyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]hafnium dichloride; rac- and meso-[ethylenebis(1-(thexyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]hafnium dichloride and rac- and meso-[dimethlylsilylenebis(3-(thexyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]hafnium dichloride; and the like.
A preferred metallocene compound according to the invention is an [ethylenebis(1-(tert-butylmethylsiloxy)indenyl)]zirconium dichloride which is racemic and has the formula (IVa), meso and has the formula (IVb), or is a mixture of a racemic compound having the formula (IVa) and a meso form compound having the formula (IVb): 
whereinxe2x80x94is methyl xe2x80x94CH3 and 
is tert.-butyl xe2x80x94C(CH3)3.
The invention also includes bridged metallocene complexes according to formula (I), M, R and B are as above in formula (I), and CpYq is a substituted (q greater than 0) or unsubstituted (q=0) cyclopentadienyl group, substituted (q greater than 0) or unsubstituted (q=0) indenyl or tetrahydroindenyl group or substituted (q greater than 0) or unsubstituted (q=0) fluorenyl or octahydrofluorenyl group. An Y-substituted CpYq ligand is connected to a CpYq ligand unsubstituted by Y (q=0) by the bridge B to give a bridged (cyclopentadienyl)(1- or 3-siloxyindenyl) ligand, a bridged (indenyl)(1- or 3-siloxyindenyl) ligand or a bridged (fluorenyl)(1- or 3-siloxyindenyl) ligand having the formula (V) or a bridged (cyclopentadienyl)(1- or 3-siloxy-4,5,6,7-tetrahydro indenyl) ligand, a bridged (indenyl)(1- or 3-siloxy-4,5,6,7-tetrahydroindenyl) ligand or a bridged (fluorenyl)(1- or 3-siloxy-4,5,6,7-tetrahydroindenyl) ligand having the formula (VI): 
Wherein D and R1-R12 and B and R4xe2x80x2-R7xe2x80x2 are the same as in formulas (IIIa) and
Preferably R1, R2, R3, R4, R5, R6, R7, R4xe2x80x2, R5xe2x80x2, R6xe2x80x2, R7xe2x80x2, R8, R9, R10, R11 and R12 are independently hydrogen or hydrocarbyl substituents. R9 and R10 may be parts of a ring structure to form an indenyl type ligand or a fluorenyl type ligand, likewise R10 and R11 may be parts of a ring structure to form an indenyl type ligand and R11 and R12 may be parts of a ring structure to form an indenyl type ligand or a fluorenyl type ligand. D is preferably silicon. R1 and R2 are preferably alkyl or aryl substituents and R3 is preferably an alkyl substituent. Preferred bridge B is a C1 or C2 alkylene or a C7-C8 arylalkylene radical or a C1-C8 organic silicon radical. If B is an alkylene or arylalkylene radical, the metallocene is 1-siloxy substituted. If B is a silylene radical, the metallocene is 3-substituted. Particularly preferred bridged (cyclopentadienyl)(1- or 3-(siloxy)indenyl) and (cyclopentadienyl)(1- or 3-(siloxy)-4,5,6,7-tetrahydroindenyl) ligands include 2-(cyclopentadienyl)-2-(1- or 3-(siloxy)indenyl)propane and 2-(cyclopentadienyl)-2-(1- or 3-(siloxy)-4,5,6,7-tetrahydroindenyl)propane ligands; and the like.
Preferred bridged (cyclopentadienyl)(1- or 3-(siloxy)indenyl) and (cyclopentadienyl)(1- or 3-(siloxy)-4,5,6,7-tetrahydroindenyl) metallocenes according to the present invention also include: isopropylidene[(cyclopentadienyl)(1-(siloxy)indenyl)]zirconium dichloride and isopropylidene[(cyclopentadienyl)(1-(siloxy)-4,5,6,7-tetrahydroindenyl)]zirconium dichloride.
The invention also includes novel unbridged metallocene catalysts having the formula (VII): 
Wherein CpYq and R are as above. Rxe2x80x2 is defined for R and Cpxe2x80x2Yxe2x80x2 is as defined for CpY. Preferably CpYq and Cpxe2x80x2Yxe2x80x2q are substituted indenyl ligands having the formula (VIII) or substituted tetrahydroindenyl ligands having the formula (IX): 
Where D, R1, R2, R3, R4, R5, R6, R7, R8, R4xe2x80x2, R5xe2x80x2, R6 and R7xe2x80x2 are the same as in formula V and R15 is one of a hydrogen, a halogen, or a substituted or unsubstituted C1-C10 hydrocarbyl group. R6 and R7 may be cyclized in an aromatic or aliphatic 6-C ring. R5 and R6 may likewise by cyclized in an aromatic or aliphatic 6-C ring. R4 and R5 may likewise be cyclized in an aromatic or aliphatic 6-C ring. The same applies for pairs of R4xe2x80x2-R7xe2x80x2 (aromatic) or single groups of R4xe2x80x2-R7xe2x80x2 (aliphatic). R1 and R2 may also be cyclized in an aliphatic 5 ring or 6 ring.
Especially preferred for CpYq or Cpxe2x80x2Yxe2x80x2q of formula (VIII) and formula (IX) are 1-siloxyindenyl or 1-siloxy-4,5,6,7-tetrahydroindenyl ligands, where R4, R5, R6, R7, R8 and R15 are hydrogen, alkyl or aryl substituents. D is preferably silicon. R1 and R3 are preferably alkyl or aryl substituents and R2 is preferably an alkyl substituent.
Particularly preferred unbridged 1-(siloxy)indenyl and 1-(siloxy)-4,5,6,7-tetrahydroindenyl ligands include as present 1-(tert-butyldimethylsiloxy)indenyl; 1-(thexyldimethylsiloxy)indenyl; 1-(tert-butyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl; and 1-(thexyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl ligands.
Preferred unbridged 1-(siloxy)indenyl and 1-(siloxy)-4,5,6,7-tetrahydroindenyl metallocenes according to the present invention include: rac- and meso-[bis(1-(tert-butyldimethylsiloxy)indenyl)]zirconium dichloride; rac- and meso-[bis(1-(thexyldimethylsiloxy)indenyl)]zirconium dichloride; rac- and meso-[bis(1-(tert-butyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]zirconium dichloride; rac- and meso-[bis(1-(thexyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]zirconium dichloride; and the same hafnium compounds such as: rac- and meso-[bis(1-(tert-butyldimethylsiloxy)indenyl)]hafnium dichloride; rac- and meso-[bis(1-(thexyldimethylsiloxy)indenyl)]hafnium dichloride; rac- and meso-[bis(1-(tert-butyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]hafnium dichloride; rac- and meso-[bis(1-(thexyldimethylsiloxy)-4,5,6,7-tetrahydroindenyl)]hafnium dichloride; and the like.
The invention also relates to a 3-substituted indene compound, which has the general formula (X): 
wherein: D is an element of Group 14 of the Periodic Table (IUPAC); R1, R2 and R3 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or at least two of R1, R2 and R3 form together with D a C4-C20 ring structure; R14 is a four atom chain forming an unsubstituted or substituted, further non-fused or further fused, homo(iso)cyclic or heterocyclic, unsaturated or saturated, aliphatic or aromatic six-membered ring; R15 and R16 are the same or different and are one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, one of R15 and R16 may be a bridge atom or group B to a cyclopentadienyl, indenyl, tetrahydroindenyl, fluorenyl or octahydrofluorenyl group, one of R15 and R16 may together with R17 form a C5-C8 aliphatic ring, provided that one of R15 and R16 is hydrogen; and R17 is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group or a group as defined for said group xe2x80x94Oxe2x80x94DR1R2R3.
Preferably, the 3-substituted indene compound according to formula (X) has the formula (XI): 
wherein R1, R2, R3, R15, R16 and R17 are the same as above, R4, R5, R6 and R7 are the same or different and each is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, at least two adjacent groups of R4-R7 may form at least one aromatic C6 ring, or at least two groups of R4-R7 may form at least one aliphatic C5-C8 ring.
According to one embodiment, the 1- or 3-substituted indene compound according to formulas (X) and (XI) has the general formula (XII): 
wherein R1, R2, R3, R1xe2x80x2, R2xe2x80x2 and R3xe2x80x2 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or at least two of R1, R2 and R3 form together with D a C4-C20 ring structure or at least two of R1xe2x80x2, R2xe2x80x2 and R3xe2x80x2 form together with Dxe2x80x2 a C4-C20 ring structure, D and Dxe2x80x2 are independently selected from Group 14 of the Periodic Table (IUPAC), R4, R5, R6, R7, R9, R10, R11 and R12 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, at least two adjacent groups of R4-R7 or R9-R12 may form at least one aromatic C6 ring, at least two groups of R4-R7 or R9-R12 may form at least one aliphatic C5-C8 ring, R17 is the same as above (formula X) and R17xe2x80x2 is as defined for R17, and B is a C1-C10 alkylene, a C2-C8 silylene or a C1-C10 alkylene-C2-C8 silylene bridge.
In formula (XII) D and Dxe2x80x2 are preferably silicon. Independently, R4, R5, R6, R7, R9, R10, R11, R12, R8 and R13 in formula (XII) are preferably hydrogen. The bridge B is preferably ethylene or dimethyl silylene.
The present invention also relates to a process for the preparation of a 3-substituted indene compound. The process is substantially characterized in that a 3-indanone compound is reacted in a solvent with a base and a halogen compound XDR1R2R3 to form a 3-DR1R2R3-substituted indene according to the following reaction scheme (XIII): 
wherein R4, R5, R6 and R7 are the same or different and each is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, at least two adjacent groups of R4-R7 may form at least one aromatic C6 zing, or at least two groups of R4-R7 may form at least one aliphatic C5-C8 ring, and R17 is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group or the same or different group xe2x80x94Oxe2x80x94DR1R2R3; D is an element of Group 14 of the Periodic Table (IUPAC); R1, R2 and R3 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or at least two of R1, R2 and R3 form together with D a C4-C20 ring structure, and X is a halogen.
In the method according to scheme (XIII) the base is preferably diazabicycloundecene (DBU) and the chlorosilane is independently and preferably tert-butyldimethylchlorosilane, thexyldimethylchlorosilane or cyclohexyldimethylchlorosilane. In scheme (XIII), R4, R5, R6 R7 and R17 are preferably hydrogens.
The invention relates to the whole process of preparing bridged 1- or 3-(siloxy) indenyl metallocenes and 1- or 3-(siloxy)-4,5,6,7-tetrahydroindenyl metallocenes by using the following reaction scheme (XIV) (disclosed for indenyl metallocene, only): 
wherein: D is an element of Group 14 of the Periodic Table (IUPAC), R1, R2 and R3 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or at least two of R1, R2 and R3 form together with D a C4-C20 ring structure; B is a C1-C10 alkylene, a C2-C8 silylene or a C1-C10 alkylene-C2-C8 silylene; each X is independently a halogen; M is a transition metal of Group 4 of the Periodic Table (IUPAC); R or each same or different R is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group a C1-C12 organosilicon group, or two R form together with M a C4-C20 metallocyclic ring structure; R4, R5, R6 and R7 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 by drocarbyl group, a substituted or unsubstituted C1-C10 by drocarbylo, group, a C1-C12 organosilicon group, at least two adjucent groups of R4-R7 may form at least one aromatic C6 ring or at least two groups of R4-R7 may form at least one aliphatic C5-C8 ring; and R17 is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group or the same or different group xe2x80x94Oxe2x80x94DR1R2R3.
In the process according to scheme (XIV), D is preferably silicon. R1, R2 and R3 are preferably the same or different and are each an unsubstituted C1-C10 hydrocarbyl group, preferably wherein two of R1, R2 and R3 are linear C1-C4 alkyl groups such as a methyl group and one of R1, R2 and R3 is a branched C3-C10 alkyl group such as an isopropyl group, a tert-butyl group or a terthexyl group, a C5-C8 cycloalkyl group such as a cyclohexyl group, or a C6 aryl group such as a phenyl group.
In scheme (XIV), B is preferably ethylene or dimethylsilylene and, independently, X is preferably chlorine or bromine. M is preferably zirconium.
Finally the invention relates to the use of the above described metallocene compounds for the polymerization (homo- and copolymerization) of ethylenically unsaturated monomers, preferably olefins such as ethylene, propylene and higher xcex1-olefins. Monomers and comonomers with more than one double bond may also be used.
Appropriate cocatalysts in the polymerization include alkylaluminum compounds, alkyl aluminoxanes such as methylaluminoxane, modified methylaluminoxane or higher aluminoxanes such as tetraisobutyl aluminoxane, hexaisobutyl aluminoxane, etc. Other cocatalysts which may be used include Lewis or protic acids, such as B(C6F5)3 or [PhNMe2H]+B(C6F5)4xe2x80x94, which generate cationic metallocenes with compatible non-coordinating anions in the presence or absence of alkylaluminum compounds.
All operations were carried out in argon or nitrogen atmosphere using standard Schlenk, vacuum or glove box techniques. Solvents were dried and distilled under argon prior to use. The 1H and 13C NMR spectra were recorded in CDCl3 or CD2Cl2 solution using JEOL JNM-LA400 or JEOL-A500 NMR spectrometer and referenced against tetramethylsilane or the residual protons of the deuterated solvents. Direct electron ionization mass spectra (EIMS) were obtained on a Varian VG-7070E or a Varian-8000 mass spectrometer.